docs: def _handleCtrlZ(self):
          """ Handler for CTRL+Z keypresses """
          if self._typingSms:
              self.serial.write(''.join(self.inputBuffer))
              self.serial.write(self.CTRL_Z_CHARACTER)
              self._typingSms = False
              self.inputBuffer = []
              self.cursorPos = 0
              sys.stdout.write('\n')
              self._refreshInputPrompt()